Cancer Genetics

One out of every three Americans will develop cancer during their lifetime. Many of us have one or more family members affected by cancer. The good news is that about 90 percent is sporadic and caused by a many factors, including genetic and environmental influences.

Approximately 5 to 10 percent of cancer is inherited. Individuals with a genetic predisposition will have a higher chance of developing cancer within their lifetime and at an earlier age. Genetic testing can help determine whether a family has a hereditary cancer syndrome.

Individuals who have genetically higher risks to develop certain cancers are recommended to follow high-risk cancer surveillance and management programs to reduce their risk or prevent cancer from occurring.

Characteristics of hereditary cancer susceptibility include:

  • The same or related types of cancer in two or more close relatives on the same side of the family (close relatives are parents, siblings, children, grandparents, grandchildren, aunts, uncles, nieces and nephews)
  • Cancer in multiple generations
  • An early age at diagnosis (usually under age 50)
  • Multiple primary tumors or bilateral cancer (like cancer in both breasts)
  • A pattern of cancer consistent with a specific hereditary cancer syndrome (e.g., breast and ovarian or colon and uterine)

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